将一个数组拆分为相同长度的多个数组
let arrSliceSameLength = function(orgArr, size) {
size = parseInt(size);
if (isNaN(size) || size < 1 || size >= orgArr.length) {
return orgArr;
}
let newArr = [];
for (let i = 0, len = orgArr.length; i < len; i += size) {
newArr.push(orgArr.slice(i, i+size));
}
return newArr;
}
//example:
let arr = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'];
arrSliceSameLength(arr, -1);
arrSliceSameLength(arr, 0);
arrSliceSameLength(arr, 5);
arrSliceSameLength(arr, 9.9);
arrSliceSameLength(arr, 26);
arrSliceSameLength(arr, 'doorgod');
//知识点
Array.prototype.slice();
//slice() 方法返回一个从开始到结束（不包括结束）选择的数组的一部分浅拷贝到一个新数组对象，原始数组不会被修改
//arr.slice(begin, end);
//begin,end参数可选，为负数表示从原数组倒数第几个开始或结束。结果包含begin,不包含end
String.prototype.slice() //用法类似
